title: In silico genetic robustness analysis of secondary structural elements in the miRNA gene.
abstract: Genetic robustness, insensitivity of the phenotype facing genetic mutations, is a fundamental and ubiquitously observed property of biological systems. In this study, we investigate the genetic robustness of the structural elements within native miRNA genes on a genome-wide scale. MicroRNAs (miRNAs) are a large family of endogenous noncoding RNAs that regulate gene expression at the posttranscriptional level. We examine the neutrality of the structural element in 1082 native pre-miRNAs from six species and demonstrate that the structural elements in native pre-miRNAs exhibit a significantly higher level of genetic robustness in comparison with structural elements within random pseudo pre-miRNAs. Hence, this excess robustness of structural elements in pre-miRNAs goes beyond the intrinsic robustness of the stem-loop structure. Furthermore, we show that it is not a by-product of a base composition bias. Interestingly, our data also demonstrate a difference in increased levels of average neutrality between structural elements. Remarkably, differential genetic robustness between structural elements is observed in both native and pseudo pre-miRNAs. Our results are much in agreement with previous experimental observations, and suggest that the genetic robustness of secondary structural elements in native pre-miRNAs, under different evolutionary selection pressures, may evolve due to its own selective advantage.
authors.affiliation: Beijing Institute of Radiation Medicine, Beijing, 100850, China.
authors.forename: Wenjie
authors.initials: W
authors.lastname: Shu
authors.forename: Ming
authors.initials: M
authors.lastname: Ni
authors.forename: Xiaochen
authors.initials: X
authors.lastname: Bo
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Zheng
authors.forename: Shengqi
authors.initials: S
authors.lastname: Wang
mesh_terms: D000465:Algorithms; D000818:Animals; D003198:Computer Simulation; D019143:Evolution, Molecular; D006801:Humans; D008390:Markov Chains; D051379:Mice; D035683:MicroRNAs / Q000737:chemistry* / Q000235:genetics*; D008957:Models, Genetic; D009690:Nucleic Acid Conformation; D051381:Rats
chemical_list: D035683:MicroRNAs